A Marine CH-53E Super Stallion helicopter was damaged during a hard landing at Camp Bastion, Afghanistan June 1, according to new data released by the Marine Corps.

The chopper was with Marine Heavy Helicopter Squadron 466, a unit based at Marine Corps Air Station Miramar, Calif., and currently deployed to Bastion. It was completing a nighttime transport mission in support of operations in Helmand province, Marine officials said, with five crew members and 13 passengers aboard. The hard landing took place around 9:45p.m. local time.

Two of the Super Stallion’s passengers received minor injuries in the hard landing, but were returned to duty shortly afterward, said 1st Lt. Garth Langley, a Marine spokesman for Regional Command Southwest, out of Camp Leatherneck, Afghanistan.

Langley would not comment on the damage to the aircraft itself, saying the incident remained under investigation. But the Naval Safety Center, which first reported the incident, classified it as a Class A Mishap, meaning the aircraft sustained at least $1 million worth of damage.

Officials would not comment on whether the actions of pilot or crew were being investigated, or when the investigation into the incident might be complete. Marine Corps Times has submitted a Freedom of Information Act request to learn more.

This recent incident comes amid a recent streak of Marine Corps aircraft crashes and other serious incidents. The last two months have seen four of the five major Marine aircraft accidents that have taken place this year.

The streak began May 9, when an AV-8B harrier from Marine Corps Air Station Yuma, Ariz. crashed outside Phoenix. The pilot ejected safely, but the plane was destroyed. Ten days later, an MV-22B Osprey Crew Chief based out of Marine Corps Air Station New River, N.C. died during a training flight when he fell out of the back of the aircraft. And days after the Super Stallion’s hard landing, on June 4, another Yuma-based Harrier crashed during a day flight. Again, the pilot ejected successfully.

Still, the aviation mishap rate for the Marine Corps is still below average for the year, with five to date. Last year the Marines had nine Class A aircraft mishaps, with an average of nearly 10 since 2002.